[Form 4] Quanterix Corp Insider Trading Activity

Rhea-AI Filing Summary

Quanterix Corp (QTRX) insider purchase by CFO: The filing shows Sriram Vandana, Chief Financial Officer, acquired 4,150 shares of Quanterix common stock on 09/12/2025 at $4.79 per share. After the transaction Vandana beneficially owned 87,200 shares in total, which the filing notes includes 72,447 restricted stock units. The Form 4 was submitted with a signature executed by an attorney-in-fact on 09/15/2025. The document records a single non-derivative purchase and lists no derivative transactions or additional amendments.

Positive

• CFO purchase disclosed, showing transparency in insider activity
• Post-transaction ownership specified (87,200 shares) with breakdown including restricted stock units
• Filing includes required details (date, price, amount) consistent with Section 16 reporting

Negative

• No information on total outstanding shares provided, so transaction materiality cannot be determined from this filing alone

Insights

Financial Analyst

TL;DR: Company CFO purchased 4,150 shares at $4.79, increasing reported beneficial ownership to 87,200 shares.

The trade is a straightforward, non-derivative acquisition by the Chief Financial Officer. The filing discloses the total post-transaction ownership and explicitly states that 72,447 of the reported shares are restricted stock units, clarifying the composition of beneficial ownership. There are no derivative transactions reported and no amendments noted. From a market-impact perspective the filing does not quantify the transaction relative to outstanding shares, so materiality to shareholders cannot be assessed from this form alone.

Corporate Governance Expert

TL;DR: Routine insider purchase disclosure showing RSU holdings; filing appears compliant and complete for reported items.

The Form 4 identifies the reporting person, role (CFO), relationship to the issuer, transaction date, price, and resulting beneficial ownership, and includes an explanatory note about restricted stock units. The signature was provided via attorney-in-fact as permitted. The filing contains the required data fields for a Section 16 report and reports no dispositions or derivative activity. It presents no governance red flags based solely on the disclosed entries.

SEC Form 4

FORM 4

UNITED STATES SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP

Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934
or Section 30(h) of the Investment Company Act of 1940

OMB APPROVAL

OMB Number:			3235-0287
Estimated average burden
hours per response:			0.5

Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).

1. Name and Address of Reporting Person^*

Sriram Vandana

(Last) (First) (Middle)

C/O QUANTERIX CORPORATION

900 MIDDLESEX TURNPIKE

(Street)

BILLERICA MA 01821

(City) (State) (Zip)

2. Issuer Name and Ticker or Trading Symbol
Quanterix Corp [ QTRX ]

5. Relationship of Reporting Person(s) to Issuer
(Check all applicable)

	Director		10% Owner
X	Officer (give title below)		Other (specify below)
	Chief Financial Officer

3. Date of Earliest Transaction (Month/Day/Year)
09/12/2025

4. If Amendment, Date of Original Filed (Month/Day/Year)

6. Individual or Joint/Group Filing (Check Applicable Line)

X	Form filed by One Reporting Person
	Form filed by More than One Reporting Person

Table I - Non-Derivative Securities Acquired, Disposed of, or Beneficially Owned
1. Title of Security (Instr. 3)	2. Transaction Date (Month/Day/Year)	2A. Deemed Execution Date, if any (Month/Day/Year)	3. Transaction Code (Instr. 8)		4. Securities Acquired (A) or Disposed Of (D) (Instr. 3, 4 and 5)			5. Amount of Securities Beneficially Owned Following Reported Transaction(s) (Instr. 3 and 4)	6. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	7. Nature of Indirect Beneficial Ownership (Instr. 4)
			Code	V	Amount	(A) or (D)	Price
Common Stock	09/12/2025		P		4,150	A	$4.79	87,200(1)	D

Table II - Derivative Securities Acquired, Disposed of, or Beneficially Owned (e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security (Instr. 3)	2. Conversion or Exercise Price of Derivative Security	3. Transaction Date (Month/Day/Year)	3A. Deemed Execution Date, if any (Month/Day/Year)	4. Transaction Code (Instr. 8)		5. Number of Derivative Securities Acquired (A) or Disposed of (D) (Instr. 3, 4 and 5)		6. Date Exercisable and Expiration Date (Month/Day/Year)		7. Title and Amount of Securities Underlying Derivative Security (Instr. 3 and 4)		8. Price of Derivative Security (Instr. 5)	9. Number of derivative Securities Beneficially Owned Following Reported Transaction(s) (Instr. 4)	10. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	11. Nature of Indirect Beneficial Ownership (Instr. 4)
				Code	V	(A)	(D)	Date Exercisable	Expiration Date	Title	Amount or Number of Shares

Explanation of Responses:

1. Includes 72,447 restricted stock units.

Remarks:

	/s/ Brian Keane, as Attorney-in-Fact	09/15/2025
	** Signature of Reporting Person	Date
Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.
* If the form is filed by more than one reporting person, see Instruction 4 (b)(v).
** Intentional misstatements or omissions of facts constitute Federal Criminal Violations See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a).
Note: File three copies of this Form, one of which must be manually signed. If space is insufficient, see Instruction 6 for procedure.
Persons who respond to the collection of information contained in this form are not required to respond unless the form displays a currently valid OMB Number.

FAQ

What did Quanterix (QTRX) CFO Sriram Vandana report on Form 4?

The Form 4 reports that CFO Sriram Vandana acquired 4,150 shares of Quanterix common stock on 09/12/2025 at $4.79 per share.

How many Quanterix shares does the reporting person own after the transaction?

After the reported purchase the filing states the reporting person beneficially owned 87,200 shares, which includes 72,447 restricted stock units.

Were any derivative securities reported in this Form 4 for QTRX?

No. The Form 4 lists only a non-derivative purchase of common stock and shows no derivative transactions.

When was the Form 4 signed and who signed it?

The filing shows a signature executed by Brian Keane, as Attorney-in-Fact on 09/15/2025.

Does the Form 4 state whether the transaction was part of a plan or automatic sale/purchase program?

No such plan or automatic transaction designation is included in the provided content; the filing lists a single purchase with code P.